While the association with major depression and depressive symptoms thus was consistent in samples across different ethnicities, this did not hold true for incident late-life depression. The association did not replicate in the Rotterdam study (N=3512) (Hofman et al., 2007) where subjects older than 55 years of age and free of dementia were screened with the CES-D at baseline and two follow up time points (Luijendijk et al., 2008). A case-control analysis was performed by comparing subjects who developed depressive disorders and depressive syndromes at follow up time points (N=438) with individuals without clinically relevant depressive symptoms (N=3074) (mean age SD of cases: 72.7 ± 7.4 and controls: 73.9 ± 8.3). None of the investigated SNPs reached significant association. The average age of 72 years at which the index depressive episode in the Rotterdam sample was diagnosed is substantially older than the average age in the combined German discovery sample and recurrent depression sample (50.4 ± 13.9 years), the Dutch ERF sample (48.7 ± 15.0 years) and the African-American sample (39.3 ± 13.7 years). In fact, in the other samples
